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Plant Diseases/Questions Answered by Expert John Cawly
| Subject | Date Asked |
| Pachira Aquatica trouble ? | 2/9/2012 |
| Q: We have a Pachira Aquatica plant (Money tree?) which is growing fine with new green leaves on top. ... A: Your advice was exactly correct. In low light conditions, nutrients are not needed. Also, too much ... | |
| Pachira Aquatica trouble ? | 2/6/2012 |
| Q: We have a Pachira Aquatica plant (Money tree?) which is growing fine with new green leaves on top. ... A: These plants are usually pretty durable and disease free. This species is native to tropical ... | |
| apple | 2/2/2012 |
| Q: How to prevent my apple trees root being rotten.I have lost my apple trees due to root failure.Is ... A: I am sorry to say that once a pathogen infects the root systems, there is little you can do to save ... | |
| Brown leaves on tomato plants | 1/18/2012 |
| Q: Tomato leaves are discoloring and looking sick and not growing to full size. They have plenty of ... A: These symptoms are classic for a tomato (or tobacco) virus. The lesions (yellowing and dying spots) ... | |
| Marigold disease | 1/11/2012 |
| Q: I love Marigold. Each year I plant marigold in full sun near borders to give color to my yard. They ... A: I am very sorry for not answering sooner. Since I am not an expert on insects, I am afraid that I ... | |
| arboricola plant disease | 1/10/2012 |
| Q: We've had this plant for over a decade. It's about 6' and has white spider web like spots on it.How ... A: I am curious which "arboricola" plant species you are talking about? Is this commonly called the ... | |
| creosote mulch | 1/2/2011 |
| Q: Would it be helpful to use creosote branches and leaves as a mulch or organic amendment to hold ... A: From the phrasing of your question, I am not sure of what you are speaking of. If you are speaking ... | |
| tree bark turned black | 9/2/2010 |
| Q: There are several dying maple trees in my neighborhood. The bark has turned a uniform flat black ... A: This is most likely a fungal infestation. There are many types of fungi that specialize in ... | |
| brugmansia problem | 6/2/2010 |
| Q: I bought 32 brugmansia, angel trumpets, this spring and 8 are showing a curling of the leaves, is it ... A: It is hard to say with so little information. Plants' leaves can curl with many environmental ... | |
| Ivy disease | 6/1/2010 |
| Q: My indoor ivy plant is dying. Seems to be dry but watering is not helping. I have noticed a web ... A: you probably have an infestation of spider mites, which produce characteristic webs. Without a ... | |
| Black eyed susans ( RUDEBEKIA) | 4/28/2008 |
| Q: We have black eyed susans planted at various places on our property, and on every one of them, our ... A: The most common pests/diseases that affect Rubeckia species are: aphids, which suck sap from the ... | |
| aphis | 4/25/2008 |
| Q: i want to ask if Permethrin ( C21H20Cl2O3 ) is efficent against green aphis of pomegranate tree or ... A: There are many methods that can be used to control aphid populations. Some are as simple as ... | |
| Shrub Disease | 4/24/2008 |
| Q: My shrub in front of house is 4 feet tall...It started turning browm on one spot last year now it is ... A: Once thought to be aphids, adelgids are fluid-feeding insects that feed on coniferous species. The ... | |
| whould you please help me ? | 4/23/2008 |
| Q: as you can see in attached pictures that I sent to your email I have a plant but I don't know It's ... A: The plants you have are azaleas, and they appear to be healthy to me. The leaves may have a small ... | |
| plant disease | 4/21/2008 |
| Q: My outdoor pansies have black spots on their leaves and some of them are dying. My aloe vera was ... A: Have you had an unusually wet spring? These conditions provide ideal conditions for fungal spore ... | |
| Viburnum - Leaves Yellowing, | 4/20/2008 |
| Q: I have 6 new leatherback Viburnum planted in the early fall of last year (2007). I live in Norther ... A: I apologize for taking so long to answer; there has been illness in the family, and I have been ... | |
| Baby lemon tree--what's wrong with it? | 4/19/2008 |
| Q: When my family was in vacation in Florida this past summer, I brought home a baby lemon tree (We ... A: The small bumps are scale insects, a very common insect pest in houseplants. The fuzz may be a ... | |
| Red Tip trees | 4/18/2008 |
| Q: I have a couple of res tips trees in my yard and they have developed a fungi on their leaves (it ... A: I apologize for not answering sooner; there has been illness in the family, and I have fallen ... | |
| Nats in Mass Cane Floor plant | 4/16/2008 |
| Q: I have a beautiful Mass Cane plant that has tiny nat looking bugs. This is my second one with the ... A: These are probably fungus gnats. They are roughly the same size as fruit flies, and are dark in ... | |
| dessert rose | 4/14/2008 |
| Q: My friend gave me a huge dessert rose but some of the roots are mushy, can I pull it out of the pot ... A: In cases of root rot (which might be the case with your plant), root pruning is sometimes effective, ... | |
| king palm disease | 3/26/2008 |
| Q: I am a landscape designer who placed eight King Palms on a job July 2007(over 100 degrees at time of ... A: It could very well be soot mold. Certain sucking insects prefer the succulent new growth (aphids, ... | |
| king palm disease | 3/25/2008 |
| Q: I am a landscape designer who placed eight King Palms on a job July 2007(over 100 degrees at time of ... A: My best hunch is that it is a combination of stress from planting, heat, and perhaps even nutrient ... | |
| Peace Lilly | 3/24/2008 |
| Q: I received a very large healthy Peace Lilly as a gift. It seemed to be doing very well untill I ... A: First, a photo of the plant would be very, very helpful. If you would like, you can send a photo to ... | |
| Camellia leaves turned almost black | 3/22/2008 |
| Q: We have several Camellia bushes in our yard and this year we noticed the leaves turning very dark, ... A: These are signs typical of sooty mold, a fungal infestation caused (usually) by sucking insects ... | |
| schefflera tree | 3/21/2008 |
| Q: I bought a schefflera tree about 3 months ago. It has done pretty well adjusting to the light ... A: This is symptomatic of a root rot disease. The first thing to do is stop watering the plant at all. ... | |
| ficus sap | 3/20/2008 |
| Q: I checked for insects as indicated in a previous response, there aren't any. Half of the tree's ... A: I have checked the log, and I don't find a question from you that I have answered. So, I am ... | |
| Small Fruit on Lemonade Tree | 3/19/2008 |
| Q: My lemonade tree is in a good sunny position all day - subject to some ocean wind but for over 5-7 ... A: G'Day Trevor, It is great to hear from you "down under". Admittedly, I am in a climate that makes ... | |
| dwarf pine | 3/18/2008 |
| Q: I have a 10yr old dwarf pine tree which turn all brown last summer and is still brown today,,no ... A: It is unusual for a pine to lose all of its needles. Unlike deciduous trees, pines drop their ... | |
| Calamondin orange gummosis? | 3/17/2008 |
| Q: I have a very healthy looking 7 foot calamondin orange tree that is about 10 years old. This tree is ... A: Root Rot Gummosis in citrus is usually caused by soil microbes, Phytophthora parasitica or ... | |
| October glory maple tree | 3/15/2008 |
| Q: I have a 4" diameter tree that the bark is cracking and peeling off, What would cause this problem? A: I wouldn't be so concerned about the bark cracking and peeling unless you see other problems such as ... | |
| Need help identifying Meyer lemon tree problem | 3/14/2008 |
| Q: I live in central Texas (Austin area) and planted a lemon tree last spring. It was fine all spring ... A: The pine bark mulch really shouldn't be a problem as the citrus trees generally like an acid ... | |
| Dieffenbachia leaf curling | 3/13/2008 |
| Q: Why are the leaves on my dieffenbachia are curling inward? A: There are many things that can cause the leaves to "curl". It is hard to say. The most common ... | |
| Umberella plant | 3/12/2008 |
| Q: i have had my umbrella plant for about 1o years and it as suddenly developed what look like aphids ... A: Here are some notes about aphids. They reproduce very, very quickly because they need no males for ... | |
| shrubs | 3/11/2008 |
| Q: leaves of photinia are spotted and dropping. Indian hawthorne on other side of yard doing the same ... A: Since both the photinia and hawthorne are in the Rose family, it is most likely that your plants ... | |
| brown spots on stems and leaves of my schefflera | 3/10/2008 |
| Q: I have a schefflera plant that I've had for 10 years. over the past month or so I've noticed these ... A: These are typical symptoms and signs of a scale insect infestation. The brown spots that you see ... | |
| Yucca stem | 3/8/2008 |
| Q: My Yucca houseplant appears to have a rotting stem. The plant consists of one long branch (I guess ... A: If I understand your problem, you are trying to save the remaining root system of the plant. ... | |
| dracena corn plant | 3/7/2008 |
| Q: My corn plant tips are turning yellow and brown.Also, one of the bottom leaves has faded to yellow. ... A: One of the best ways to improve the humidity is to use a room humidifier. They can be purchased at a ... | |
| dracena corn plant | 3/6/2008 |
| Q: My corn plant tips are turning yellow and brown.Also, one of the bottom leaves has faded to yellow. ... A: Just calm down! Take a deep breath, nothing is wrong. Your Dracena is experiencing some changes in ... | |
| house plants | 3/5/2008 |
| Q: I have a plant a tree of some sort the problem is i have a yellowy light green fiddlehead or spore ... A: Your message suggests that this recurs after having once removed it? Is that right? Fiddleheads ... | |
| dead branches at bottom of willow | 3/3/2008 |
| Q: I have a lovely weeping willow that we planted in wetlands about 6 years ago. It has grown ... A: Yes, it is normal that older branches will sometimes break off. All is good if the new shoots are ... | |
| Black leaves and stems on my Actinidia Arguta Issai | 3/2/2008 |
| Q: I hope you can help me. I've recently bought a small example of the above plant, and it was in need ... A: First, I must admit that I am very envious of Londoners and their relatively mild weather. Here in ... | |
| Aloe Plant Problems | 3/1/2008 |
| Q: I live in S. California by the beach. I have 2 aloe plants that are about 2.5 feet tall. A few ... A: This sounds very much like a bacterial or fungal infection. Does the tissue become mushy as it ... | |
| Orange tree doing poorly | 2/28/2008 |
| Q: My orange tree has a thin canopy, some yellowing leaves and some roots are coming up to the ... A: This sounds like a pH or secondary- or micronutrient problem to me. If the soil pH is too alkaline, ... | |
| Ficus Tree | 2/27/2008 |
| Q: Cawly - I have had a ficus tree for 10 years. It is about 7 feet tall. We moved and the tree ... A: I wouldn't be so concerned just yet. Ficus (benjamina?) trees are notoriously sensitive to changes ... | |
| Meyer Lemon recovery from scales | 2/26/2008 |
| Q: I have a 4 foot Meyer Lemon that battled a very frusturating scale infestation last summer (the ... A: The very, very best advice I can give you is to try to maintain the scale insect population until ... | |
| meyer lemon white spots | 2/24/2008 |
| Q: I have seen several questions regarding white spots on Meyer lemon leaves...but not an answer to get ... A: It is really hard to help without more information. Did the specks appear suddenly? Do they appear ... | |
| Meyer lemon tree leaf disease | 2/21/2008 |
| Q: My 4 year old Meyer lemon tree has leaves that curl, get Spider webs and fall off. It does not seem ... A: When you say the leaves "curl up", do you mean that they are deformed leaves, or do you mean that ... | |
| jade problems | 2/20/2008 |
| Q: my jade plant is drooping and i just found some tiny white spots on some of the leaves and stems. ... A: Sounds like spider mites. Spider mites are almost impossible to see with the naked eye. They are ... | |
| What is wrong with my potted palm? | 2/19/2008 |
| Q: About half the leaves on the tree have disappeared. There are tiny white "balls" that cover nearly ... A: What do these little "balls" look like? How big are they? Are they smooth? Are they fuzzy? Are ... | |
| Dwarf Lemon and Lime trees | 2/18/2008 |
| Q: I have a dwarf lemon and a lime tree. They are about twenty years old and produce well each year. I ... A: That is hard to say without knowing the pedigree of the plants. Generally, you can grow plants from ... | |
| Meyer lemon tree leaf disease | 2/17/2008 |
| Q: My 4 year old Meyer lemon tree has leaves that curl, get Spider webs and fall off. It does not seem ... A: Are these container grown lemons or are they grown in the ground? There are many types of ... | |
| peace lily disease | 2/15/2008 |
| Q: My peace lily at work was doing fine. Very green healthy new leaves. I took a close look and one of ... A: Not likely that the fertilizer sticks have anything to do with any disease. As far as the 'sesame ... | |
| shiny residue | 2/13/2008 |
| Q: I have a 7 ft. jasmine that we move outside in the warm weather and overwinter in my sun room. It ... A: Shirlene, The hard residue that you are seeing might just be a scale insect infestation. If the ... | |
| Ficus tree with sap droppings | 2/10/2008 |
| Q: We have an older Ficus tree, about 2/3 is dead with a light sap droppings about the floor and ... A: I wouldn't be ready to give up yet. Species of Ficus have a milky white sap sometimes referred to ... | |
| fig tree soil infested with knats | 2/9/2008 |
| Q: We were recently given a fig tree and the soil is covered with very small knats. What is safe to ... A: If the gnats are located at the soil line, or hovering just above, what you are dealing with is a ... | |
| Peace Lily | 2/8/2008 |
| Q: I have 3 lilies outside in pots. I live in southen FL. The leaves are turning black.The pots are ... A: When you say peace lily are you talking about the "spathe" lily? Check out the following website: ... | |
| Anthurium "Cleopatra" | 2/6/2008 |
| Q: I purchased and potted this plant, Anthurium "Cleopatra", about 2 months ago and the new leaves ... A: When purchasing potted plants, it is notoriously difficult to know how long that plant has been in ... | |
| 1/16 | 2/4/2008 |
| Q: Truthfully I'm not sure whether this infestation is the fault of the dwarf banana tree and three ... A: Regarding the fungus gnat infestation, fly paper can reduce the adult population, and that is a ... | |
| English Ivy Deficiency | 2/3/2008 |
| Q: MY English Ivy plant is not growing as it should. It starts to branch out and then the end just dies ... A: I am not clear on what is actually happening. What are the symptoms presented before the branch ... | |
| 1/16" teeny flying black bug investation | 1/31/2008 |
| Q: Truthfully I'm not sure whether this infestation is the fault of the dwarf banana tree and three ... A: These small flies are most likely fungus gnats. They usually do no harm to the plants, but can be ... | |
| lemon tree worm and wierd things | 1/29/2008 |
| Q: My indoor lemon tree has lots of tiny yellowish worms on it, but what is weird is there are also ... A: I am not an entomologist, but pictures would really help. E-mail them to me at: ... | |
| Clivia infestation | 1/27/2008 |
| Q: I have (what I think is known as) a Clivia: Long dark green leaves with beautiful red (mine is) ... A: I am not an entomologist, so I don't have a great deal of knowledge with respect to specific pests. ... | |
| Jade with some kind of disease | 1/24/2008 |
| Q: I have about 8 Jades in my bow window & various other plants the big jade is about 25yrs old. ... A: As a precaution, segregate the healthy plants from the one showing these symptoms. A couple of ... | |
| cottony cushion scale on acer | 1/23/2008 |
| Q: i love in rome (italy) & have cottony cushion scale on my acer. what is the best way to treat this ... A: The one thing that you didn't mention was whether this is an ornamental indoor species, or an ... | |
| white leaves | 1/22/2008 |
| Q: i recently bought a rosemary plant.the leaves where ok but a little pale.now it is covered in small ... A: As they say, a picture is worth a thousand words. Can you perhaps send a photo to me? You can send ... | |
| Deodara Ceder | 1/21/2008 |
| Q: my problem is my neighbors deodara cedar has been dropping its needles on my roof for years and for ... A: Having to deal with the plant residue of neighbors plants is a consequence of living in the city, I ... | |
| Defoliated trees | 1/19/2008 |
| Q: 55 of my mautre peppercorn (Schinus areira = Schinus molle var. areira) trees were defoliated by a ... A: It is often the case that when plants are treated with herbicides, the leaves drop fairly quickly, ... | |
| house plant problem | 1/17/2008 |
| Q: I have a large plant I believe to be of the palm tree variety. It has fuzzy white stuff on the ... A: Yes, it is quite possible that what you are seeing is a fungal infestation. Powdery mildew, ... | |
| indoor ficus | 1/15/2008 |
| Q: We have an indoor ficus that appears to be about 5 years old or so,(we were told it was braided only ... A: Examine the tree very, very carefully for scale insects. These are small (1/8 inch - 3.0 mm) oval ... | |
| night blooming cereus | 1/15/2008 |
| Q: I have a cereus plant that is several years old and has been doing well until recently. The leaves ... A: I have had a night-blooming cereus for years, and I had a similar problem. This species is a desert ... | |
| honeysuckle with yellow leaves & brown spots | 1/14/2008 |
| Q: I live in the high desert in california my honeysuckles i planted this spring are now getting yellow ... A: High Desert in the wintertime! Must be lovely weather. Upon examination of your leaves, are ... | |
| house plant problem | 1/13/2008 |
| Q: I have a large plant I believe to be of the palm tree variety. It has fuzzy white stuff on the ... A: sorry for the delay in answering, but we are beginning the spring semester at the university. It is ... | |
| Oleander tree | 1/11/2008 |
| Q: I purchased an oleander tree in the summer of 2007. I do not know a great deal about them other than ... A: Examine your tree very, very carefully for small (1/8 inch, 3 mm) oval to circular flat "disks". ... | |
| umbrella plant | 1/9/2008 |
| Q: I have an umbrella plant was keeping it indoors and all but one stem remains how do i care for it to ... A: The very best remedy for an ailing plant is a good light environment. If you are in a climate that ... | |
| plant reaction to harm | 1/9/2008 |
| Q: I have read an article stating that plants can react to damage by releasing specific hormones. ... A: Just because you don't see a physical reaction, don't think that the plant is not reacting ... | |
| "Stagnant" Lemon Tree | 1/5/2008 |
| Q: The pot is 6" in diam. and 6" tall. The tree is about 18" tall (above the soil). It was beautiful ... A: Sorry for the delay in answering, I overlooked the e-mail somehow. I apologize. First, I would ... | |
| finding fsp of fusarium oxisporum | 1/4/2008 |
| Q: i have a fusarium oxisporum caused disease on cactus and I like to find its fsp . could you please ... A: The only report I could find on fusarium oxysporum disease in cacti is in the American ... | |
| plant disease | 1/3/2008 |
| Q: My name is Melanie and I live in Colorado. I have a ton of house plants that do very well. This ... A: I am certain that what you are experiencing is a scale insect infestation. These are mobile only as ... | |
| hybiscus bush | 1/2/2008 |
| Q: live in s. fl. have older hybiscus bush ,planted facing n e. blooms beautiful full blooms.al of a ... A: The problem is with water conductivity into the plant from the roots. If you have been thoroughly ... | |
| disease | 10/2/2007 |
| Q: what is powder mildew ? A: Powdery mildew is a fungal disease that affects many plant species. It is characterized by the ... | |
| lilacs | 10/1/2007 |
| Q: Your question was "something drilled a hole in the base of my lilac, never saw the culprit, plant ... A: What size is the hole in the lilac? There are a number of bees and wasps that can bore holes in ... | |
| Majasty Palm | 9/30/2007 |
| Q: I have numerous potted Majasty Palms. The ones on the front porch healthy...the one on the screened ... A: I thought I had answered your question, but perhaps not. I am sorry if you have not received an ... | |
| Oak leaf problems | 9/29/2007 |
| Q: I have several oaks, Sand live oak (Quercus geminata) I am pretty sure. I just notices a lot of ... A: Give me a day or two to do some initial research on this. There are several things that could be ... | |
| Magnolia x Soulangiana, Rosea | 9/26/2007 |
| Q: I live in Florida and have a Magnolia x Soulangiana rosea, which is only two years old, in my yard. ... A: Wenn ich fragen darf, sind Sie vielleicht Deutsche? I am not sure that the leaf problem is ... | |
| aloe plant | 9/25/2007 |
| Q: I have two questions about my aloe plant. one is similar to a question I just read about mold on the ... A: I love your descriptions! I am not sure from your description whether you have any disease or not. ... | |
| hedge dying | 9/25/2007 |
| Q: my box ornamental hedges have been lovely over the years now at random one will start turning ... A: What is your feeding and watering regimen on these hedges? Yellowing can be a symptom of low ... | |
| gardenia | 9/23/2007 |
| Q: i live in south florida, i have a gardenia, due to the very hot weather i keep it inside near a ... A: First, examine the plant's leaves very, very carefully for scale insects. These often appear as ... | |
| Antique climbing rose buses | 9/22/2007 |
| Q: And I have a problem with one that I just cant figure out ..it is not growing as fast as my other ... A: August is not really the optimal time to transplant roses, so there may be an extended period of ... | |
| lilac tree disease | 9/22/2007 |
| Q: My lilac tree's leaves are turning white. My mail lady said she thought the tree has a disease. What ... A: Lilac trees at this time of year (northern hemisphere?) are usually infested with powdery mildew. ... | |
| brown spots on king palm leaves | 9/21/2007 |
| Q: We have eleven king palm trees in our yard. One of them, which is planted on a lawn develops rusty ... A: Ahmad, Send me a photo at my e-mail posted on the instructions. From your brief description, it ... | |
| Apple tree disease | 9/20/2007 |
| Q: I have a 15 yo old apple tree that has a disease that has affected almost every apple tree I have ... A: I sincerely apologize for taking so long to answer your question. Time has a way of getting away ... | |
| Sago spots | 9/19/2007 |
| Q: John, I am in Central Texas and have a sago palm that has little brown spots down the center of each ... A: Most likely what you are seeing is a scale insect infestation. They appear as small flat, oval to ... | |
| Wisteria | 9/18/2007 |
| Q: I have a wisteria spp. which has been in situ for 7 years, it is on a south facing wall and four ... A: I have never known a wisteria to be that sensitive to handling. They are notoriously vigorous, to ... | |
| Phlox dying for no apparent reason | 9/16/2007 |
| Q: I hope you can help me discover why my beautiful and totally healthy "David" phlox just started to ... A: This may be the result of a root rot infection, usually caused by a bacterium or fungus. Phlox are ... | |
| lemonade tree | 9/15/2007 |
| Q: how ever now that spring is here and it had flowers I am worried because the leaves are starting to ... A: If the leaves on your lemon tree are curling, there are three common possibilities: 1. Some insect ... | |
| >> Jade Plant Problem << | 9/15/2007 |
| Q: I have big yellow mushrooms and mold growing in my Jade Plant pot. Is this a plant disease and how ... A: Diane, These mushrooms and molds are natural decomposers; they use the decaying organic matter in ... | |
| yucca plant | 9/12/2007 |
| Q: My yucca plant keeps getting spots on the lower leaves, then turns yellow and dies. The stem of the ... A: Dorian, I am not sure that there is anything "wrong" with your Yucca plant. (Yucca cane?) Yuccas ... | |
| Jade Plant drooping | 9/12/2007 |
| Q: My Jade, out of no where, began to droop, (that is, all the major stems, the ones that are tall ... A: If you have found root rot, you have done the right thing by removing the old potting mix from the ... | |
| worms | 9/11/2007 |
| Q: I have been finding these small blue/grey worms all over my creeping jenny. They are eating holes ... A: There are several plants called "Creeping Jenny", but the one I am familiar with is _Lysimachia ... | |
| Jade Plant drooping | 9/10/2007 |
| Q: My Jade, out of no where, began to droop, (that is, all the major stems, the ones that are tall ... A: If your plants are green and healthy, then do not use any sprays or supplements. "Messenger" is a ... | |
| boxwoods drained of color | 9/10/2007 |
| Q: I have many boxwoods and euonymous that are being drained of color and dropping leaves. I'm frantic ... A: Since you don't mention any insects, etc. I can only speculate that you have seen none on these ... | |
| Bradford Pear Problems | 9/9/2007 |
| Q: I think I may know the answer to this question, but I want to make sure. I have about 8 Bradford ... A: I think you have diagnosed the problem correctly, but it is very unusual that all of the leaves have ... | |
| Foam / Frothing Sweet Basil plant? | 9/7/2007 |
| Q: I bought some Sweet Basil cuttings at my local farmer's market (they aren't certified organic but ... A: The white froth on your plants is called spittle and is produced by spittlebugs (nymphs of the adult ... | |
| problem with Viburnum Chindo | 9/6/2007 |
| Q: 6 days ago I planted several Viburnum Chindo (5gal size) in my yard. They were very good specimens ... A: Craig, I am sorry that I haven't answered your question earlier, I must have overlooked it somehow. ... | |
| Sago Palm | 9/6/2007 |
| Q: Whit spots appearing on leaves like a fugus can it be treated? What do I need to do to stop it or ... A: Please examine the spots very, very closely. Sago Palms are particularly susceptible to scale ... | |
| Lime tree | 9/4/2007 |
| Q: The peel on the limes that I just picked are very thick, approx. 1/4 inch or more, with the inside ... A: There is wide variation in the thickness of the rinds in citrus fruit. This is particularly the ... | |
| unwanted mushrooms | 9/3/2007 |
| Q: I just got back from a my long weekend to find mushrooms growing in my potted succulent plant (i ... A: Mushrooms are nature's decomposers, and they are absolutely harmless. The fungal spores find a ... | |
| grape vine curling and browning | 9/3/2007 |
| Q: I purchased a grape vine about six months ago. Recently, about a few weeks ago, I noticed that the ... A: Depending on your climate, such browning could be environment-related. This is the time of year in ... | |
| Ming Aralia very sick, over wattering has lead to near demise, or so it seems | 9/2/2007 |
| Q: I have a wonderful Ming Aralia, which was, until about a week or so ago, quite healthy. I admit that ... A: The most important thing to remember is that no additive will have much effect when a plant has no ... | |
| lemon tree dots | 9/2/2007 |
| Q: I have a lemon tree which has got brown dots similar to an other question I saw you answering here, ... A: What you describe are classic symptoms of scale infestation. As you can remove the small "dots", ... | |
| Fruitless Mulberry Disease? | 9/1/2007 |
| Q: We have a mature Fruitless Mulberry tree in our backyard and noticed a problem with it lately. At ... A: What you describe sounds like Bacterial Wetwood disease. This is a common disease that affects the ... | |
| Ming Aralia very sick, over wattering has lead to near demise, or so it seems | 9/1/2007 |
| Q: I have a wonderful Ming Aralia, which was, until about a week or so ago, quite healthy. I admit that ... A: Micah! All I can say is WOW! You have taken some very careful steps in treating this plant. My ... | |
| Brown Spots, Yellow Leaves | 6/14/2007 |
| Q: A month ago I planted a chitalpa in New Mexico. It was doing fine until a couple of days ago. Now ... A: Brown spots and chlorosis (yellowing of the leaves) are both symptoms of nutrient deficiencies ... | |
| Meyer lemon tree - diseased | 6/14/2007 |
| Q: We were given a Meyer lemon tree for Christmas. It stayed indoors until just recently. While still ... A: The problem is some sort of sucking insect (aphids, whitefly, scale insect, or mealybug.) All of ... | |
| Meyer Lemon Tree | 6/13/2007 |
| Q: I have this lemon tree for about 4 yrs. and after spending the winter indoors the leaves on the ... A: My first thought is that there is a nutrient deficiency. As the sunlight increases, so does the ... | |
| white growth on pine tree | 6/13/2007 |
| Q: My father has a small pine tree (about 1 1/2ft high) growing on his balcony. He waters the tree ... A: I would suggest that the tree has been overwatered. Normally, there is no need to keep a pine tree ... | |
| dying vinca minor | 6/12/2007 |
| Q: Our well established vinca minor is dying in large patches. No sign of stem rot or insects; no dark ... A: This is puzzling. My first thought is that there is something interfering with the water uptake, ... | |
| Crepe Myrtles | 6/12/2007 |
| Q: We recently received two crepe myrtle bushes from a friend. I immediately replanted them using ... A: You most likely have a whitefly infestation. The "syrup" is a byproduct called honeydew which is ... | |
| White Hardened Nodules under tree leaves | 6/11/2007 |
| Q: I have several deciduous trees in my back yard which have white round nodules on the underside of ... A: Leaf galls can be caused by many things, but the most likely cause are insects what use the leaves ... | |
| meyer lemon tree | 6/11/2007 |
| Q: We've had our tree forever (came with house) we've trimmed it ourselves several times but haven't ... A: It sounds as though you may need to add some nutrients to your soil, such as iron. High soil ... | |
| bug infestation | 6/10/2007 |
| Q: I live in Niagara Falls, Canada and for the past three years we have had an infestation of tiny ... A: I am sorry, but I have very little experience with "bugs". I am not an entomologist, so I am ... | |
| diseases on roses | 6/10/2007 |
| Q: My roses, this year, are withering on the new growth, turning black,and any buds dry up. We have ... A: You may be quite right. The symptoms you describe are characteristic of "fire blight" caused by ... | |
| Jade plant pests | 6/9/2007 |
| Q: John, I have a Jade tree that for years has had fine spider webs at the dirt. I assume spider ... A: Charlie, First of all, is the plant outdoors? If not, you could be having a top heavy plant because ... | |
| meyer lemon tree | 6/8/2007 |
| Q: I have a small meyer lemon tree whose leaves are not a solid green. The leaves look washed out - ... A: The longer plants remain indoors in poor light, the more pale the leaves will become. The intense, ... | |
| Yellow mushrooms in my house plants | 6/7/2007 |
| Q: There are leucocoprinus growing in all of my house plants. I noticed them in one a couple of weeks ... A: Since you know the genus of the fungus, I assume you have correctly identified it. These fungi are ... | |
| Leaf Drop | 6/7/2007 |
| Q: I am having huge problems in my garden. This summer (and last) the majority of my plants drop their ... A: I have a feeling that what you are experiencing is a pH problem. All of the plants you mention like ... | |
| diagnoses of apple tree | 6/6/2007 |
| Q: I found this black jelly on the branches of a weeping green apple tree, I first thought it was tar ... A: I need some more information. Is the slime/jelly sticky? Does it have a sweet taste? Are there ... | |
| lemon tree | 6/6/2007 |
| Q: I've had my lemon tree for a year. It has produced many wonderful lemons. Suddenly this winter the ... A: Your lemon tree can certainly go outside now, even though the temperatures may seem a bit low, all ... | |
| leaf blight/disease on victoria plum tree | 6/5/2007 |
| Q: My 3 yr old victoria plum tree,s leaves are curling in from the edges,they look as if singed,I have ... A: What you describe sounds like a very common disease, Peach Leaf Curl caused by the fungi in the ... | |
| Cycad with yellow edged-fronds | 6/4/2007 |
| Q: John - I have 3 sagos in my yard - two in front, one in back. The back one seems fine, but one of ... A: I am of the opinion that this condition is nutrient related, as you also suggest. The rain drainage ... | |
| Honeysuckle aphids | 6/3/2007 |
| Q: My gardener noticed aphids on an otherwise thriving honeysuckle. I went on the internet and read ... A: If it were only that easy to kill honeysuckles. (They have escaped from homes and gardens and ... | |
| browning edges | 6/3/2007 |
| Q: I finally found a "spider plant" and it is wonderfully full, I have hung it in my kitchen where I ... A: The spider plant can go a substantially long period of time without water, so water the plant ... | |
| shrub disease | 6/2/2007 |
| Q: I have a problems with my shrubs. I am not sure of the type of shrub (they are mature and about 4 ... A: I am reluctant to make a guess so few details. There are some common pests found in many home ... | |
| Weird leaf thing! | 6/1/2007 |
| Q: I hope you can help. We have a tree in are yard I have know idea what it is called,but it appers to ... A: I am not an entomologist, but there are many insects which use the leaves as nesting (and feeding ... | |
| moth question and jasmine tree question | 6/1/2007 |
| Q: 1. today I opened my bookcase and saw three little beige moths so I closed the glass doors and then ... A: I am sorry, but I really do not have any expertise to answer your first question. However, if the ... | |
| meyer lemon tree | 5/6/2007 |
| Q: I live in south Louisiana and I recently bought two lemon trees. One of the trees had small light ... A: There are many things that can cause the yellow splotches, including lack of nutrients. If you have ... | |
| Meyer Lemon issue | 5/5/2007 |
| Q: I have a 6 foot meyer lemon tree that lives in a pot it has black dust on top of the leaves and ... A: This is most likely a scale insect infestation. The black dust is probably sooty mold which is a ... | |
| Plant disease? | 5/5/2007 |
| Q: I have a white powdery looking substance growing on my bushes - it's on the leaves. Started last ... A: This is probably powdery mildew (a fungus), although this is a bit early. There are many fungicides ... | |
| Yucca Houseplant | 5/3/2007 |
| Q: My yucca plant is 3 trunks (short, medium and tall) each with 3 stems coming from them. The medium ... A: You probably have a Yucca Cane which is very easy to care for. If you have a "soggy" stem and a ... | |
| sago palms - white powder disease? | 5/2/2007 |
| Q: I have two older sago palms that are covered with what looks like a white powder. Both palms have ... A: This sounds like powdery mildew, but that is not usually a bit pest in cycads. I am still ... | |
| Gardenias | 5/2/2007 |
| Q: The leaves of my gardenias are turning yellow and dying on some plants in the bed I have on a bank ... A: The black powdery substance may be sooty mold. This is a fungus infestation that feeds on the ... | |
| holly trouble | 5/1/2007 |
| Q: I also live in NJ and have the same problem with my Hollys. I have nine small holly shrubs located ... A: This is most likely winter damage. To confirm this, the tips and edges of the leaves will appear ... | |
| problems with Jasmine | 5/1/2007 |
| Q: John We have a summer jasmine that is about 15 yrs old, but has hardly never flowered. Is ... A: Greetings to the UK! I am not sure of what species of Jasmine you are talking about, but the ones ... | |
| Mushrooms in Meyers (improved) Dwarf Lemon Tree | 4/29/2007 |
| Q: in my search I see that you may have answered this question before, but unfortunately I cannot find ... A: Mushrooms are a natural decomposer. The mushrooms will do no harm to your Meyer's Lemon. They ... | |
| juniper and cedar disease | 4/24/2007 |
| Q: I have noticed a white cottony substance about the size of a cue tip at the v joint on a juniper ... A: It is hard to tell with so little information. It could be many things including webs of small ... | |
| light green fungus | 4/24/2007 |
| Q: the pineapple guava tree has a light green fungus at the trunk of the tree. the tree is planted in a ... A: I am not certain that what you are seeing is a fungus. Fungi rarely are that color. There are ... | |
| sago palm | 4/22/2007 |
| Q: I read the recent posts on sago palms, but ours seems to have some different "symptoms." It's an ... A: Before I say anything, check out the following website; it contains a photo of a "flowering" cycad. ... | |
| our sago palm | 4/22/2007 |
| Q: Our Sago Palm turned crispy brown over the winter.My husband has trimmed it back in hope that it ... A: I am not overly optimistic about the future of your cycad. There may still be hope if the very ... | |
| Fine white powder on rose leaves | 4/18/2007 |
| Q: I have an indoor minature rose which I have noticed has a fine white powder like substance on the ... A: This is most likely powdery mildew, a fungal infestation. Powdery mildew is a common problem when ... | |
| CRAPE MYRTLE | 4/17/2007 |
| Q: I HAVE A POWDERY MOLD TYPE SUBSTANCE ON THE BRANCHES AND BARK OF MY CRAPE MYRTLE. A: There are several fungal diseases that produce powder-like mildew. The most common do not affect ... | |
| spider webs on gardenia buds | 4/17/2007 |
| Q: In Washington, DC, I have a gardenia plant that lives outside in the spring, summer, and inside in ... A: Love the DC area. I lived in Burke, Va. myself years ago. It sounds as though your gardenia may be ... | |
| straw with some mold | 4/16/2007 |
| Q: I have bales of straw I got last year for mulching. I found when I broke into them there was some ... A: Obviously your straw has some fungus growing in it, and that is the normal decay/recycling mechanism ... | |
| tomato leaf disease | 4/15/2007 |
| Q: newly planted tomatoes in greenhouse are showing brown blotches on leaves,think it may be mosaic ... A: The most common mosaic that affects tomato is Tobacco mosaic virus. This is characterized by ... | |
| Homework help | 4/13/2007 |
| Q: Cawly, I am doing a project in Science Class comparing plants grown in hydroponic solution to plants ... A: When plants don't have a good supply of nutrients (minerals), such as iron, magnesium, potassium, ... | |
| Holly bush problem | 4/2/2007 |
| Q: I have two holly bushes on the north side of my house. The leaves are all turning brown. I live in ... A: I am probably not the best person to ask about the holly bushes/trees. There are many fungi that ... | |
| my beautiful schefflera is dying!! :( | 4/2/2007 |
| Q: I have a schefflera, approx. 7 years old, that has enjoyed the same east-facing window during cold ... A: You probably have spider mites. If you have a handheld shower, take it to the shower and spray it ... | |
| Indoor Mini Rose Bush Disease | 4/1/2007 |
| Q: I received a mini rose bush (pink marina??) for my birthday and it has been living indoors for the ... A: It sounds like you may have powdery mildew on your mini-rose. Symptoms: Powdery mildew is named for ... | |
| Silverleaf maples in Texas | 3/31/2007 |
| Q: Trying to figure out whats going on with two maples I have. The last three years, fewer and fewer ... A: I cannot tell from your description exactly what is going on, but there is a symptom you describe ... | |
| forsythia | 3/31/2007 |
| Q: My fosythia bush seems very healthy, but it has knobby brown balls on alot of the limbs. Some are as ... A: In many cases, these small "knobs" are insect cases for developing larvae. However, if you have ... | |
| agastache disease? | 3/30/2007 |
| Q: Several varieties of agastache (cana, rupestris, etc.) have developed yellow leaves with green ... A: From the look of the interveinal chlorosis, this appears to be a nutrient deficiency. The Osmocote ... | |
| White cottony substance on majesty palm plant | 3/30/2007 |
| Q: I have a majesty palm plant I bought in December. When I purchased the plant, it needed TLC - it ... A: White cotton-like masses are most often associated with mealybugs. You can treat these with rubbing ... | |
| Meyer lemon leaf problem | 3/29/2007 |
| Q: I recently brought home three small "improved" Meyer Lemon trees. All three were potted in the same ... A: At this point, I would not stress the plants any further until they recover from transplant shock. ... | |
| Yucca plants | 3/28/2007 |
| Q: Ron from Dallas, I have several outdoor yucca, planted in partial sun. All of the plants have ... A: I am not sure what those light colored splotches could indicate. Watering yucca plants is usually ... | |
| Spanish Moss | 3/27/2007 |
| Q: I live on a 15-acre oak hammock area in Florida. Ninety percent of the trees are oaks with a mix of ... A: This is really not an area in which I have much experience, so you may try to ask another expert who ... | |
| Gardenia Plant | 3/27/2007 |
| Q: I have a gardenia plant that has a coating (very much like a webworm) on the leaves, they turn ... A: These very small, fine webs are most likely due to spider mite infestation. There are many organic ... | |
| Summer Jasmine leaf problems | 3/26/2007 |
| Q: It was going fine until about a month ago when all of a sudden it started losing ALOT of leaves. ... A: Ciao Giulia, What a wonderful place to live. I am still researching your problem. Please be ... | |
| sago palms | 3/25/2007 |
| Q: I have two sago palms we purchased in Florida last year and they have done well until recently. ... A: What you have is a scale insect infestation. This is a common problem with sago palms. The ... | |
| Rose leaves | 3/24/2007 |
| Q: My rose leaves are cut into curve shape. I cut all the leaves but next day morning again I find more ... A: This is probably due to the leaf cutter bee which uses the cut parts of the leaves as nesting ... | |
| Meyer Lemon Tree with teenie black bugs | 3/24/2007 |
| Q: We have a Meyer Lemon tree that is doing well apart from teensie black/green bugs congregating on ... A: The sticky residue is called "honeydew" and is common of sucking insects. There are many of them ... | |
| Green fungus on trunk | 3/23/2007 |
| Q: I have 2 Norway maples that have developed a green fungus on the trunks of both trees. Is there a ... A: Most likely these organisms are not fungi, but rather algae or some type of moss. These are common ... | |
| green worms | 3/23/2007 |
| Q: I have these small green worms, they are maybe 1/2 inch long and very thin. They hang from threads ... A: Can you tell me where you are located? This sounds like inchworm or cankerworm infestation. But ... | |
| meyer lemon | 3/22/2007 |
| Q: I have a large meyer lemon tree planted outside for over five years. It is wonderfully prolific but ... A: See if any of the following seems familiar. What you could be seeing is melanose on the lemons ... | |
| examination of diseases | 3/22/2007 |
| Q: How can I tell if my roses have black spot? When does it appear in the spring? A: This is a good time to be asking that question. But, the prevention of black spot is something that ... | |
| sago palm problems | 3/21/2007 |
| Q: My in-laws from Southern CA gave us a 12-15" Sago that they had been growing in their yard among ... A: Once these scale insects are dislodged from the leaf or stem, they CANNOT reattach. The only stage ... | |
| lemon tree bark disease | 3/21/2007 |
| Q: I have an older lemon tree that is developing white patches on its bark. Is this a disease and is ... A: I will have to do some more research on this one. My first thought was citrus canker, but that is ... | |
| Ficus & pests | 3/20/2007 |
| Q: from one 'Expert' (I'm in real estate) to another, thank you in advance for your time. I am nursing ... A: It is obvious that you are an avid gardener as you are right on target with your observations. As ... | |
| sago palm problems | 3/19/2007 |
| Q: My in-laws from Southern CA gave us a 12-15" Sago that they had been growing in their yard among ... A: sandi, I am out of town right now and working on my pda. You have a scale insect ... | |
| lemon tree bark disease | 3/19/2007 |
| Q: I have an older lemon tree that is developing white patches on its bark. Is this a disease and is ... A: Terry, I am out of town, and I will answer your question soon. Hi Terry, Could you be a bit ... | |
| Tomato Help | 3/13/2007 |
| Q: I was wondering if you could give some advice on my tomato plants. The leaves seem to be dieing ... A: The symptoms you describe can be due to a deficiency in calcium. Blossom End Rot is a common ... | |
| POTTING SOIL | 3/12/2007 |
| Q: even that i know that the potting soil depend highly about the plant, but if we are talking about a ... A: Any of the multi-purpose potting mixes will do well without any additions. However, when potting ... | |
| yucca disease | 3/9/2007 |
| Q: hope u can help. my yucca plant i didn't what it's genre showed a browning at the end of the ... A: When the leaf tips brown, it may be the result of chemical accumulation (revealed as white deposits ... | |
| hydrogen peroxide as plant disinfectant | 3/7/2007 |
| Q: Is it safe to use on plants? I have a nectarine with gummosis and I'm wondering if I can apply h2o2 ... A: Gummosis is a symptom of another underlying fungal infestation or bacterial infection. Without ... | |
| lemon tree | 3/5/2007 |
| Q: I live in Hayward, CA and the leaves on our lemon tree have fuzzy spots on the undersides that ... A: It sounds as though you may have a mixed infestation of mealybugs and scale insects. Both are ... | |
| spider plants | 3/5/2007 |
| Q: I own two spider plants that I am having some trouble with. They are green & growing but are ... A: Spider plants normally have a droopy appearance, but if they are not getting sufficient water into ... | |
| meye lemon | 3/3/2007 |
| Q: my meyer lemon tree has sap on the leaves and little brown spots..it is dying slowly what can I do? A: Most likely, the small brown spots are scale insects. They appear oval to round in shape, approx. 3 ... | |
| sago palm got the ick? | 2/28/2007 |
| Q: well I got a sago plam for x-mas its is a bonsai style pot.I noticed the the center of each leaf is ... A: Leaf chlorosis in cycads (sago palm) can be a symptom of magnesium deficiency. The fronds become ... | |
| Sweet Soil | 2/28/2007 |
| Q: Doc. I have a followup. If sugar dehydrates things in the soil, I get the impression that sugar ... A: Salt would have a greater effect on the plants themselves. If you live in an area that uses salt ... | |
| Sweet Soil | 2/27/2007 |
| Q: What is sweet soil and is this bad for plants or good? I am asking because of the recommendation I ... A: The term "sweet soil" is an old farmer's term to indicate an alkaline soil, i.e. one with a higher ... | |
| Roses | 2/23/2007 |
| Q: "forces the ground water including anything dissolved in the water through cell membranes"? But you ... A: Carol, Sorry if I didn't write clearly. The casparian strip is a waxy substance between the ... | |
| Snake plant bugs | 2/20/2007 |
| Q: I have a huge beautiful snake plant that has recently become infested with little black bugs, that ... A: Can you describe when and where you see the insects? Also describe the cultural conditions, i.e. ... | |
| Meyer Lemon | 2/19/2007 |
| Q: I got a healthy Meyer 12/06. The tree bloomed and set a lot of fruit. I moved the tree outside for ... A: Do you notice any scale insects on the leaves? Black soot mold is often a complication when the ... | |
| Sugar supplements! | 2/17/2007 |
| Q: My second question in connection with your recent post re sugar watering and rses: What is your ... A: There are many fungal aaaociations with plant roots. Fungi and bacteria have a tremendous ability ... | |
| Roses | 2/17/2007 |
| Q: I have two followup questions based on your recent answer about growing roses in sugar water vs. ... A: sugar molecules cannot pass through the cell membranes even if dissolved in water. sorry for the ... | |
| Mother in law or snake plant | 2/15/2007 |
| Q: After a year in water and leave that have turned yellow, can proper care turn the leaves green ... A: The Latin name for genus of the "mother-in-law" or "snake" plant is _Sempervivium_, which ... | |
| roses | 2/14/2007 |
| Q: Would roses grow faster in sugar water or regular water? A: Plants have an anatomical feature called a casparian strip in the roots which selectively admits ... | |
| White substance on clay pots. | 2/8/2007 |
| Q: How on earth do I get rid of the white moldy looking substance on the outside of all my clay pots. ... A: There are several ways to clean up the salt build up on clay pots. The first is to simply scrape it ... | |
| Massangeanna Cane has mold in the dirt | 2/5/2007 |
| Q: I just purchased a Massangeanna in Dec 2006. However it has been by the living room window on those ... A: I was surprised to see your question still in the "unanswered questions" section. I prepared an ... | |
| tiny white insects in soil | 12/13/2006 |
| Q: sorry to bother you again. but the tiny white insects that's infesting my mother's potted plants do ... A: No bother at all. The small white "rice grains" are probably the larvae of the fungus gnat. I ... | |
| tiny white insects in soil | 12/12/2006 |
| Q: the soil around the roots of my mother's potted plants are filled with lots of tiny white insects. ... A: A common problem in house plants is fungus gnat infestation. The larvae of these gnats are white ... | |
| black residue on Meyer lemon bush | 12/12/2006 |
| Q: Sorry John, I put the question in your rating. My follow up question is that when I told you my ... A: Yes, the size of this tree will make a difference in how you treat for insects. I assume that this ... | |
| black residue on Meyer lemon bush | 12/11/2006 |
| Q: I have a very large meyer lemon bush. The bush is very productive but I have had two problems in the ... A: Given the pairing of prior white fly infestation and the black residue, it strongly suggests black ... | |
| Lemon Tree Fungus? | 12/2/2006 |
| Q: I have a lemon tree in the back yard of the house we bought two years ago. The first year we got ... A: Try to give me some more information. You mention that you had first noticed "white spots" on the ... | |
| Mold on soil of a potted plant | 11/30/2006 |
| Q: I have a basil plant in a pot that I planted with potting soil. I keep it outside unless it gets ... A: Of more concern to me than the "mold" on the surface of the soil, is the wilting plant that has been ... | |
| White Powdery Substance - Ponytail Bonsai | 11/29/2006 |
| Q: Plants in my office -- most recently a ponytail bonsai, have a white powdery and fluffy like ... A: The fluffy white substance is probably related to a mealybug infestation. From time to time, I have ... | |
| peace lilly | 11/27/2006 |
| Q: john, I have a peace lilly that is slowly dying and I don't know what to do! The stems have brown ... A: Look at the underside and stems of the plant very, very carefully. What you describe is "honeydew" ... | |
| aloe vera | 11/27/2006 |
| Q: hope u can help me!! I've had my aloe vera for about 8 or 9 months now and its been growing ... A: The orientation of the Aloe vera may have something to do with the amount and direction of the light ... | |
| indoor lemon tree/plant | 11/26/2006 |
| Q: We live in South Devonshire, England and have a lemon tree/plant in a pot. The plant is about 2 ft ... A: Greetings. What you see on your lemon tree is sooty mold which caused by a fungal infestation. ... | |
| Meyer Lemon - Black Spots on young Branches | 11/26/2006 |
| Q: there are no yellow halos on the tree but there are a large number of small ants around the black ... A: What you have is a scale insect infestation. The scale insects appear as small circle to ... | |
| Meyer Lemon - Black Spots on young Branches | 11/25/2006 |
| Q: I live in Melbourne I have a 2 year old Meyer Lemon tree planted in the garden. Well drained soil ... A: There are many things that can cause black spots on lemon leaves: frosts, fungal infestations, and ... | |
| winter moths | 11/20/2006 |
| Q: Last spring my flowering crabapple never bloomed. All of its buds and many/most leaves were eaten by ... A: This is really outside my area of expertise, but I did find a very educational website about the ... | |
| lemon tree question | 11/20/2006 |
| Q: Our lemon tree has a white powdery substance under all of its leaves. Tree appears to be healthy ... A: From your description, I would first suspect a fungal infestation. Do you see any crawling white ... | |
| Meyers Lemon Tree | 11/19/2006 |
| Q: I have a Meyers lemom tree about 5 years old. I noticed that the underside of the leaves are white ... A: With regard to the curled leaves, this is usually a response to poor drainage or over-watering. ... | |
| White scale | 11/18/2006 |
| Q: What product can I use to eradicate a "white scale" on my Sago Palms A: There are many horticultural oils that can be applied that can control scale insect infestation. ... | |
| agave | 11/18/2006 |
| Q: My agave is outdoors and has been for nearly 16 years now. The inside I was referring to is the ... A: What your agaves have are symptoms and signs of bacterial disease. The translucent pulp of the ... | |
| sego palms with white dots | 11/16/2006 |
| Q: I noticed you had a question on the white specs on the leaves. I have the same problem and I also ... A: These are most likely Asian (white) scale insects. Many scale-infested cycads have yellow and brown ... | |
| Potted palm a goner? | 11/16/2006 |
| Q: I've had a potted palm for about 18 years now. The crown was dying back badly last summer, so I ... A: Sadly, the likelihood that your palm will survive is very small. It sounds as though there is some ... | |
| scale | 11/15/2006 |
| Q: I live in South Florida. Yesterday the high was about 80 degrees, and today will be more humid and ... A: You are very fortunate that in your area you can garden throughout the season. Contact your local ... | |
| marigolds and dahlia's are dying | 11/15/2006 |
| Q: My marigolds that were once thriving are now totally dying. they are in pots but outside in a flower ... A: I am afraid that your marigolds and dahlias have typical symptoms of Southern bacterial wilt, caused ... | |
| sheflera plant | 11/14/2006 |
| Q: I am looking for possible treatment for sheplera plant parsites There is a shiny sticky residue on ... A: The insects are most likely scale insects which appear as small, circular/oval (circa 3 to 5mm ... | |
| Glozinia | 11/13/2006 |
| Q: I have two Glozinia plants in my house. One has flowered for over 2 months. The other is a ... A: Before I can be of much help, I need for you to be as specific as possible in answering a few ... | |
| meyer lemon tree | 11/13/2006 |
| Q: I bought a Meyer lemon tree about 1 1/2 years ago. When I got it it had 2 lemons on it that grew and ... A: I doubt that this has anything at all to do with disease since you don't see any symptoms or signs ... | |
| pruning a snowball bush | 11/11/2006 |
| Q: We moved into our house one year ago and found that we have a snowball bush, a large not very pretty ... A: Most likely what you have is a summer-blooming hydrangea (_Hydrangea arborescens_ or _Hydrangea ... | |
| dwarf lemon tree disease | 11/11/2006 |
| Q: I received a dwarf lemon tree for Christmas 2 years ago. It had grown and filled out well. I have ... A: When you say that the "dirt" is "stuck", do you mean that there is something sticky on the leaves? ... | |
| schefflera plant | 11/9/2006 |
| Q: I have had my schefflera for over 10 years. 2 years ago I moved to my office. Lately, it has been ... A: Sorry to hear of your problem with the Schefflera. My first thought is that it is probably time to ... | |
| Meyers lemon leaves turned upside down | 11/5/2006 |
| Q: New tree planted one year ago on ocean 20 mi south of San Francisco. It gets southen exposure and ... A: First of all, if only a few leaves are affected and it is only an occasional occurrence, then I ... | |
| worms in potted palm | 11/4/2006 |
| Q: I have what look like worms with legs in a potted palm a friend gave to me. What do I need to do to ... A: I am not an entomologist, so I cannot be sure of the insect you describe. Pill bugs roll up into ... | |
| worms in potted palm | 11/3/2006 |
| Q: I have what look like worms with legs in a potted palm a friend gave to me. What do I need to do to ... A: I hope to be able to help you, but first I need some information. Was this potted palm kept ... | |
| roses | 11/3/2006 |
| Q: I have a lichen, or moss that looks like grey/green scale on my roses. How do you get rid of it. A: Most likely what you have is neither a lichen nor a moss, but rather a scale insect infestation. ... | |
| weeping cherry blossom | 10/31/2006 |
| Q: We are in spring, the blossoms are gone, the tree is full of leaves. I have rechecked the tree I do ... A: (I envy you; it is autumn here, and we are facing winter.) If this is Witches' Broom, the tuft of ... | |
| Schefflera Plant Disease | 10/30/2006 |
| Q: I have a large Schefflera Plant and the leaves are dropping off. There is a shiny sticky residue on ... A: This sticky residue is probably due to scale insect infestation. Mealybugs and scale insects are ... | |
| Jasmine | 10/29/2006 |
| Q: We are living in spain, and we have a jasmine growing over an archway. The problem seems to be that ... A: With so little information, it is very difficult to determine the cause of the leaf drop. Your ... | |
| weeping cherry blossom | 10/28/2006 |
| Q: Our weeping cherry blosson tree blossoms then gets leaves then the some of theleaves start to curl ... A: First. Can you answer a few questions for me? Do you see small tufts of leaves at the tips of the ... | |
| Date Palm | 10/25/2006 |
| Q: I have two large date palm tree's, that I have recently moved indoors. They started dropping a ... A: First of all. How large are these palms? Have you examined the fronds and stems for scale insects. ... | |
| Sago Palm Diseases | 10/18/2006 |
| Q: I have twenty plus Sago Palms that I propogated about five years ago. They are growing in Texas ... A: I discounted scale insects because you mentioned you didn't see any insects. Yes, scale insects can ... | |
| Meyer Lemon Tree Disease | 10/17/2006 |
| Q: I have had a meyer lemon tree for 1 1/2 years. The first year I had lots of lemons and blooms with ... A: it really helped. First, I would suggest that you supplement your feedings with a small amount (1 ... | |
| Meyer Lemon Tree Disease | 10/15/2006 |
| Q: I have had a meyer lemon tree for 1 1/2 years. The first year I had lots of lemons and blooms with ... A: I need a bit more information. Can you tell me where you are located? Have you repotted the tree ... | |
Plant Diseases
John Cawly
Top Expert on this page
Expertise
I can help with identification and possible treatment of plant diseases that affect houseplants and horticultural species, to include both biological (fungal, bacterial, viral, parasitic etc.) and environmental/cultural (watering, potting media, etc.) aspects.
Experience
Practical experience with a wide variety of houseplants and greenhouse plants, including cacti, euphorbia, african violets, amaryllus, and many others.
Organizations
American Phytopathology Society
American Society of Plant Biologists
American Society for Virology
Publications
Molecular Plant Microbe Interactions
Proceedings of the National Academy of Science (in print)
Rhodora -- Journal of the New England Botanical Society
Allelopathy Journal
Education/Credentials
BS, Southern Illinois University - Biological Sciences
MS, Southern Illinois University -- Biological Sciences - Genetic Engineering Specialization
PhD, University of Missouri Columbia -- Plant Microbiology and Pathology
(Viral Diseases specialization/Biotechnology Emphasis)
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